I. Field of the Invention
The present invention relates to an underwater viewing device for use with a boat.
II. Description of the Prior Art
There have been a number of previously known underwater viewing devices for use with boats, submarines, and other aquatic vehicles. While many of these devices are adapted to be positioned over the side of the boat with one end inserted in the water, still others are adapted for use in conjunction with an opening formed through the bottom of the boat hull. Such a device, for example, is described in U.S. Pat. No. 1,149,678 which issued on Aug. 10, 1915 to J. T. Parker.
These previously known underwater viewing devices of the latter type, however, suffer from a number of common disadvantages. One prime disadvantage of these previously known underwater viewing devices is that many devices are unnecessarily bulky, and therefore both expensive and space consuming. Since it is impractical to devote a major portion of the interior or most boats to an underwater viewing device, these previously known underwater viewing devices have not enjoyed widespread use or acceptance.
A still further disadvantage of the previously known underwater viewing devices is that conventionally only a sheet of glass or other fragile, transparent material is positioned across the hull opening to prevent the entry of water into the interior of the boat. These transparent sheets, however, are prone to breakage, particularly when operating the boat in rocky and/or shallow water. Breakage of the transparent sheet disadvantageously permits water to enter into the interior of the boat and will sink the boat unless the shore can be rapidly reached.
A still further disadvantage of many of these previously known underwater viewing devices is that entry of light into the interior of the viewing device interferes with the desired underwater view. Several prior known viewing devices, such as described in U.S. Pat. No. 1,371,986 which issued on Mar. 15, 1921 to F. I. Stiles, employed complex shutter or blind arrangements in order to block external light. These previously known attempts to block external light, however, are not only unduly expensive and complex in construction, but have also proved to be inadequate in operation.
A still further disadvantage of these prior devices is that a person cannot simultaneously operate the viewing device and the boat.